Fix for a crash that occured when CSNotificationView would be presented on a view controller that had it’s view not loaded yet.

Fixes #32. Usage CGSizeApplyAffineTransform in combination with an uninitialized view caused an EXC_BAD_ACCESS KERN_PROTECTION_FAILURE.
Updated to 0.4.1
Correct usage of deployment target.
Different way for checking current version as well as ignoring deprecation warnings for iOS 6 only stuff.
0.4.2
Factored out layer-stealing into a separate class `CSLayerStealingBlurView`.

Moved class extension of `CSNotificationView` into a separate file.

Introduced a protocol `CSNotificationViewBlurViewProtocol` that blur-implementations have to support.

Refs GH #37
Dropped iOS 6 support. fixes GH #40
tintColor adjustments now done in the blur implementation.
Added implementation using `UIVisualEffectView`. refs GH #39
Updated icons and added @3x versions.
Added pixelmator files of existing icons to project.
Using asset bundle instead of xcassets.
Asset bundle is now generated by CocoaPods.
Updated Podfile.
Updated to describe new requirements.
fix bundle image source of iOS 7
Moved sample project to subdirectory. Using own pod now.